diff --git a/src/riakc_utils.erl b/src/riakc_utils.erl
index 36111ba2..fba298c2 100644
--- a/src/riakc_utils.erl
+++ b/src/riakc_utils.erl
@@ -24,6 +24,7 @@
 
 -export([wait_for_list/1, characters_to_unicode_binary/1]).
 
+-spec wait_for_list(non_neg_integer()) -> {ok, list()} | {error, any()}.
 %% @doc Wait for the results of a listing operation
 wait_for_list(ReqId) ->
     wait_for_list(ReqId, []).
@@ -34,6 +35,7 @@ wait_for_list(ReqId, Acc) ->
         {ReqId, {_, Res}} -> wait_for_list(ReqId, [Res|Acc])
     end.
 
+-spec characters_to_unicode_binary(string()|binary()) -> binary().
 %% @doc Convert to unicode binary with informative errors
 %% @throws {unicode_error, ErrMsg}
 characters_to_unicode_binary(String) ->